During flight operations a number of restrictions are typically placed on aircraft operation. For example, there may be restrictions relating to minimum and maximum aircraft airspeeds and aircraft g-loading. Futhermore, it may be desirable to limit aircraft bank angle commanded by the pilot or autopilot during an engine-out takeoff. This is to reduce aircraft drag and prevent accidental stalling. Typically, this information is available from the aircraft's flight manual and is memorized by the pilot.
It may be desirable, however, to automatically limit aircraft operation commanded by the pilot in accordance with these flight restrictions. Conventionally, some aircraft have used computer controlled systems to limit maximum bank angle during an engine-out takeoff until a predetermined airspeed has been reached. Upon reaching this threshold airspeed, the maximum permissible bank angle was increased. In the event the airspeed decreased below this threshold, the maximum bank angle remained at the upper limit.
Conventionally, a number of aircraft automatic control systems have been disclosed. For example, U.S. Pat. No. 3,837,603 by Schultz et al discloses an automatic flight control system for controlling the aircraft so as to maintain runway centerline alignment during takeoff, landing, and go-around when an outboard engine is not functioning. In addition, in U.S. Pat. No. 4,129,275 by Gerstine et al there is disclosed automatic flight control apparatus for aircraft which includes a hysteresis function for generating a bias signal when an airspeed delta exceeds a predetermined limit.